1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

use std::cell::Cell;
use std::cmp::Ordering;

use base::id::HistoryStateId;
use dom_struct::dom_struct;
use js::jsapi::Heap;
use js::jsval::{JSVal, NullValue, UndefinedValue};
use js::rust::{HandleValue, MutableHandleValue};
use net_traits::{CoreResourceMsg, IpcSend};
use profile_traits::ipc;
use profile_traits::ipc::channel;
use script_traits::{ScriptMsg, StructuredSerializedData, TraversalDirection};
use servo_url::ServoUrl;

use crate::dom::bindings::codegen::Bindings::HistoryBinding::HistoryMethods;
use crate::dom::bindings::codegen::Bindings::LocationBinding::Location_Binding::LocationMethods;
use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
use crate::dom::bindings::error::{Error, ErrorResult, Fallible};
use crate::dom::bindings::inheritance::Castable;
use crate::dom::bindings::reflector::{reflect_dom_object, DomObject, Reflector};
use crate::dom::bindings::root::{Dom, DomRoot};
use crate::dom::bindings::str::{DOMString, USVString};
use crate::dom::bindings::structuredclone;
use crate::dom::event::Event;
use crate::dom::eventtarget::EventTarget;
use crate::dom::globalscope::GlobalScope;
use crate::dom::hashchangeevent::HashChangeEvent;
use crate::dom::popstateevent::PopStateEvent;
use crate::dom::window::Window;
use crate::script_runtime::{CanGc, JSContext};

enum PushOrReplace {
    Push,
    Replace,
}

/// <https://html.spec.whatwg.org/multipage/#the-history-interface>
#[dom_struct]
pub struct History {
    reflector_: Reflector,
    window: Dom<Window>,
    #[ignore_malloc_size_of = "mozjs"]
    state: Heap<JSVal>,
    #[no_trace]
    state_id: Cell<Option<HistoryStateId>>,
}

impl History {
    pub fn new_inherited(window: &Window) -> History {
        let state = Heap::default();
        state.set(NullValue());
        History {
            reflector_: Reflector::new(),
            window: Dom::from_ref(window),
            state,
            state_id: Cell::new(None),
        }
    }

    pub fn new(window: &Window) -> DomRoot<History> {
        reflect_dom_object(Box::new(History::new_inherited(window)), window)
    }
}

impl History {
    fn traverse_history(&self, direction: TraversalDirection) -> ErrorResult {
        if !self.window.Document().is_fully_active() {
            return Err(Error::Security);
        }
        let msg = ScriptMsg::TraverseHistory(direction);
        let _ = self
            .window
            .upcast::<GlobalScope>()
            .script_to_constellation_chan()
            .send(msg);
        Ok(())
    }

    /// <https://html.spec.whatwg.org/multipage/#history-traversal>
    /// Steps 5-16
    #[allow(unsafe_code)]
    pub fn activate_state(&self, state_id: Option<HistoryStateId>, url: ServoUrl, can_gc: CanGc) {
        // Steps 5
        let document = self.window.Document();
        let old_url = document.url().clone();
        document.set_url(url.clone());

        // Step 6
        let hash_changed = old_url.fragment() != url.fragment();

        // Step 8
        if let Some(fragment) = url.fragment() {
            document.check_and_scroll_fragment(fragment, can_gc);
        }

        // Step 11
        let state_changed = state_id != self.state_id.get();
        self.state_id.set(state_id);
        let serialized_data = match state_id {
            Some(state_id) => {
                let (tx, rx) = ipc::channel(self.global().time_profiler_chan().clone()).unwrap();
                let _ = self
                    .window
                    .upcast::<GlobalScope>()
                    .resource_threads()
                    .send(CoreResourceMsg::GetHistoryState(state_id, tx));
                rx.recv().unwrap()
            },
            None => None,
        };

        match serialized_data {
            Some(data) => {
                let data = StructuredSerializedData {
                    serialized: data,
                    ports: None,
                    blobs: None,
                };
                let global_scope = self.window.upcast::<GlobalScope>();
                rooted!(in(*GlobalScope::get_cx()) let mut state = UndefinedValue());
                if structuredclone::read(global_scope, data, state.handle_mut()).is_err() {
                    warn!("Error reading structuredclone data");
                }
                self.state.set(state.get());
            },
            None => {
                self.state.set(NullValue());
            },
        }

        // TODO: Queue events on DOM Manipulation task source if non-blocking flag is set.
        // Step 16.1
        if state_changed {
            PopStateEvent::dispatch_jsval(
                self.window.upcast::<EventTarget>(),
                &self.window,
                unsafe { HandleValue::from_raw(self.state.handle()) },
                can_gc,
            );
        }

        // Step 16.3
        if hash_changed {
            let event = HashChangeEvent::new(
                &self.window,
                atom!("hashchange"),
                false,
                false,
                old_url.into_string(),
                url.into_string(),
                can_gc,
            );
            event
                .upcast::<Event>()
                .fire(self.window.upcast::<EventTarget>(), can_gc);
        }
    }

    pub fn remove_states(&self, states: Vec<HistoryStateId>) {
        let _ = self
            .window
            .upcast::<GlobalScope>()
            .resource_threads()
            .send(CoreResourceMsg::RemoveHistoryStates(states));
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-pushstate>
    /// <https://html.spec.whatwg.org/multipage/#dom-history-replacestate>
    fn push_or_replace_state(
        &self,
        cx: JSContext,
        data: HandleValue,
        _title: DOMString,
        url: Option<USVString>,
        push_or_replace: PushOrReplace,
    ) -> ErrorResult {
        // Step 1
        let document = self.window.Document();

        // Step 2
        if !document.is_fully_active() {
            return Err(Error::Security);
        }

        // TODO: Step 3 Optionally abort these steps
        // https://github.com/servo/servo/issues/19159

        // TODO: Step 4

        // Step 5
        let serialized_data = structuredclone::write(cx, data, None)?;

        let new_url: ServoUrl = match url {
            // Step 6
            Some(urlstring) => {
                let document_url = document.url();

                // Step 6.1
                let new_url = match ServoUrl::parse_with_base(Some(&document_url), &urlstring.0) {
                    // Step 6.3
                    Ok(parsed_url) => parsed_url,
                    // Step 6.2
                    Err(_) => return Err(Error::Security),
                };

                // Step 6.4
                if new_url.scheme() != document_url.scheme() ||
                    new_url.host() != document_url.host() ||
                    new_url.port() != document_url.port() ||
                    new_url.username() != document_url.username() ||
                    new_url.password() != document_url.password()
                {
                    return Err(Error::Security);
                }

                // Step 6.5
                if new_url.origin() != document_url.origin() {
                    return Err(Error::Security);
                }

                new_url
            },
            // Step 7
            None => document.url(),
        };

        // Step 8
        let state_id = match push_or_replace {
            PushOrReplace::Push => {
                let state_id = HistoryStateId::new();
                self.state_id.set(Some(state_id));
                let msg = ScriptMsg::PushHistoryState(state_id, new_url.clone());
                let _ = self
                    .window
                    .upcast::<GlobalScope>()
                    .script_to_constellation_chan()
                    .send(msg);
                state_id
            },
            PushOrReplace::Replace => {
                let state_id = match self.state_id.get() {
                    Some(state_id) => state_id,
                    None => {
                        let state_id = HistoryStateId::new();
                        self.state_id.set(Some(state_id));
                        state_id
                    },
                };
                let msg = ScriptMsg::ReplaceHistoryState(state_id, new_url.clone());
                let _ = self
                    .window
                    .upcast::<GlobalScope>()
                    .script_to_constellation_chan()
                    .send(msg);
                state_id
            },
        };

        let _ = self.window.upcast::<GlobalScope>().resource_threads().send(
            CoreResourceMsg::SetHistoryState(state_id, serialized_data.serialized.clone()),
        );

        // TODO: Step 9 Update current entry to represent a GET request
        // https://github.com/servo/servo/issues/19156

        // Step 10
        document.set_url(new_url);

        // Step 11
        let global_scope = self.window.upcast::<GlobalScope>();
        rooted!(in(*cx) let mut state = UndefinedValue());
        if structuredclone::read(global_scope, serialized_data, state.handle_mut()).is_err() {
            warn!("Error reading structuredclone data");
        }

        // Step 12
        self.state.set(state.get());

        // TODO: Step 13 Update Document's latest entry to current entry
        // https://github.com/servo/servo/issues/19158

        Ok(())
    }
}

impl HistoryMethods<crate::DomTypeHolder> for History {
    /// <https://html.spec.whatwg.org/multipage/#dom-history-state>
    fn GetState(&self, _cx: JSContext, mut retval: MutableHandleValue) -> Fallible<()> {
        if !self.window.Document().is_fully_active() {
            return Err(Error::Security);
        }
        retval.set(self.state.get());
        Ok(())
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-length>
    fn GetLength(&self) -> Fallible<u32> {
        if !self.window.Document().is_fully_active() {
            return Err(Error::Security);
        }
        let (sender, recv) = channel(self.global().time_profiler_chan().clone())
            .expect("Failed to create channel to send jsh length.");
        let msg = ScriptMsg::JointSessionHistoryLength(sender);
        let _ = self
            .window
            .upcast::<GlobalScope>()
            .script_to_constellation_chan()
            .send(msg);
        Ok(recv.recv().unwrap())
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-go>
    fn Go(&self, delta: i32, can_gc: CanGc) -> ErrorResult {
        let direction = match delta.cmp(&0) {
            Ordering::Greater => TraversalDirection::Forward(delta as usize),
            Ordering::Less => TraversalDirection::Back(-delta as usize),
            Ordering::Equal => return self.window.Location().Reload(can_gc),
        };

        self.traverse_history(direction)
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-back>
    fn Back(&self) -> ErrorResult {
        self.traverse_history(TraversalDirection::Back(1))
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-forward>
    fn Forward(&self) -> ErrorResult {
        self.traverse_history(TraversalDirection::Forward(1))
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-pushstate>
    fn PushState(
        &self,
        cx: JSContext,
        data: HandleValue,
        title: DOMString,
        url: Option<USVString>,
    ) -> ErrorResult {
        self.push_or_replace_state(cx, data, title, url, PushOrReplace::Push)
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-history-replacestate>
    fn ReplaceState(
        &self,
        cx: JSContext,
        data: HandleValue,
        title: DOMString,
        url: Option<USVString>,
    ) -> ErrorResult {
        self.push_or_replace_state(cx, data, title, url, PushOrReplace::Replace)
    }
}